How do San Francisco homes get heat? As I understand it, it gets cool enough in SF to require heating a lot of the time. If gas is banned, a lot of people switch from gas to electric heat? Straining an already strained grid?
Definitely not "a lot of the time". The coldest it gets is maybe 40°F on a particularly chilly winter night - with a well-insulated house you hardly even need central heat.
2. 40°F is 4°C. That's cold. What do you expect the indoor temperature to be in those conditions, without heating?
I'm currently living in a well insulated German new build, and over this last winter was wearing a T-shirt inside while it was actively snowing outside. The average combined power consumption of all things in this property is about 500 watts. It would be lower, but we didn't know how to correctly configure some of it in the first 6 months.